(1) Field of the Invention
The present invention pertains to a child resistant closure between a container and a cap that also comprises a separate safety lock ring. The lock ring is mounted over the neck of the container and the cap is mounted on the neck of the container and engages with a pair of lock clasps on opposite sides of the safety lock ring. Finger pads on opposite sides of the safety lock ring must be squeezed and compressed by one hand of the user while the cap is rotated on the container neck by the other hand of the user in order to separate the cap from the container. The safety lock ring is designed to be employed with container and cap closure assemblies of at least two different sizes, which eliminates a need for separate safety lock rings for the two different sizes of containers and caps and reduces their manufacturing costs.
(2) Description of the Related Art
Child resistant closures are often employed on containers having potentially harmful contents such as pharmaceutical drugs, household cleaning liquids and household insecticides, to name only a few applications. One example of the construction of a child resistant closure between a container and cap includes a locking mechanism on the container that must be moved by one hand of the user while the cap is removed from the container by the other hand of the user. The requirement of using two hands to perform two movements on the container and cap not only perplexes children attempting to remove the cap from the container, but also many adults.
The typical child resistant closure is incorporated into the construction of the container and the cap. In plastic containers and caps, component parts of the child resistant closure mechanisms are molded onto both the containers and the caps. Incorporating a child resistant closure mechanism in the construction of the container and the cap increases the costs of manufacturing the container and cap over the costs of manufacturing a container and cap that do not incorporate a child resistant closure.
In addition, because the container and cap are manufactured with the child resistant closure mechanism as part of their constructions, the child resistant closure mechanism cannot be removed from the container and cap when the child resistant closure is not required or desired. Individuals who do not have children that purchase products contained in container and cap assemblies incorporating child resistant closures often find the presence of the child resistant closure to be an inconvenience.
What would overcome these disadvantages associated with child resistant closures employed on container and cap assemblies is a child resistant closure apparatus that could be removed from the container and cap assembly when desirable. In addition, a child resistant closure apparatus that could be employed with container and cap assemblies of more than one size would reduce the costs associated with manufacturing the two different sizes of container and cap assemblies comprising child resistant closure mechanisms.
The child resistant closure apparatus of the present invention overcomes the disadvantages associated with prior art child resistant closures by providing a closure mechanism that can be removed from the container and cap assembly when desired. The child resistant closure apparatus also provides a safety lock ring that can be employed with at least two different size container and cap assemblies, thereby providing a reduction in manufacturing costs by providing a single part that can be employed with two different container and cap assemblies. These advantages are provided by the child resistant closure apparatus of the invention which is basically comprised of a container, a cap removably attachable to the container and a safety lock ring that is removably attachable to the container. In the preferred embodiment of the invention each of these three component parts are manufactured of a plastic material, as is conventional in the art.
The container has a hollow interior volume and an opening in the container provides access to the interior volume. A cylindrical neck surrounds the opening. The container neck exterior surface has an attachment mechanism formed thereon that is complementary to an attachment mechanism of the cap. The container neck is formed with a pair of arcuate ridges that project outwardly from the container neck on opposite sides of the container neck. The container neck is also formed with a pair of ribs that project outwardly from the container neck just below the ridges.
The lock ring has a cylindrical sidewall that is dimensioned to pass easily over the container neck with the sidewall spaced radially outwardly from the container neck. A pair of finger pad portions of the sidewall project radially outwardly from opposite sides of the sidewall. A pair of clasps project radially inwardly from the finger pads to distal ends of the clasps. The distal end of each clasp is formed with a hook that projects upwardly from the clasp. The lock ring is also formed with a pair of flanges that project radially inwardly from opposite sides of the sidewall at positions that are oriented 90xc2x0 relative to the lock ring clasps.
The lock ring is removably attached to the container neck by passing the lock ring over the neck and positioning the lock ring flanges on the tops of the container neck ridges. Pushing the lock ring downwardly causes the lock ring to resiliently deflect moving the lock ring flanges radially outwardly and passing the flanges over the container neck ridges. The lock ring flanges engage beneath the container neck ridges thereby removably attaching the lock ring to the container neck.
In the preferred embodiment of the invention the cap is a cap of a trigger sprayer that removably attaches the trigger sprayer to the container. However, the cap of the child resistant closure need not removably attach a separate component to the container and can be employed only to provide a removable closure over the opening of the container neck. The cap has a cylindrical skirt that is dimensioned to fit over the container neck and inside of the lock ring. The interior of the cap skirt is formed with an attachment mechanism complementary to the attachment mechanism of the container neck. In addition, the cap skirt interior is provided with a pair of lugs on opposite sides of a cap. Each lug is formed with a cam surface and a stop surface.
In attaching the cap to the container neck the cap is moved downwardly over the neck and is rotated relative to the neck in the manner conventional with screw threaded attachment mechanisms or bayonet type attachment mechanisms. As is conventional, the cap is rotated in a clockwise direction over the container neck which causes the cam surfaces of the cap lugs to come into engagement with the hook portions of the lock ring clasps. The rotational movement of the cap causes the clasp hook portions of the lock ring to slide over the cam surfaces. The resiliency of the lock ring enables the clasp hook portions to move radially inwardly as they slide over the lug cam surfaces. When the clasp hooks of the lock ring have passed over the cap lug cam surfaces the resiliency of the lock ring causes the clasp hooks to snap into place adjacent the cap lug stop surfaces. The positioning of the clasp hooks of the lock ring adjacent the cap lug stop surfaces prevents the cap from being rotated in the counterclockwise direction to remove the cap from the container neck.
To remove the cap from the container neck it is necessary to first manually squeeze the finger pads on the opposite sides of the lock ring compressing the resiliency of the lock ring. This causes the clasp hooks of the lock ring to move radially inwardly toward each other displacing them from their previous positions adjacent the cap lug stop surfaces. With the clasp hooks displaced from the cap lug lock surfaces, the cap can now be rotated with the other hand of the user in a counterclockwise direction to remove the cap from the container neck.
The lock ring of the child resistant closure apparatus of the invention is dimensioned to be employed with two different size container and cap assemblies. In the preferred embodiment the lock ring may be employed with a container and cap assembly having a 24 mm diameter container neck and a 28 mm diameter container neck. However, container and cap assemblies having other neck dimensions may be employed by changing the dimensions of the lock ring. By enabling use of a single size lock ring with two different size container and cap assemblies to provide those assemblies with a child resistant closure apparatus, the manufacturing costs of the two different sizes of container and cap assemblies is reduced.
In addition, because the lock ring is removably attached to the container by the resiliency of the lock ring and the engagement of the lock ring flanges beneath the container neck ridges, the lock ring can be removed from the container if desired. This enables the child resistant closure apparatus to be removed from the container and cap assembly where it is desired that the container and cap assembly not have a child resistant closure apparatus.